/* Copyright  2009-2010
   @Author
   Richard Changde Yin            e-mail yinchangde@hotmail.com

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/**
 * @filename: sj_tmp_table.h
 */
#ifndef __SJ_TMP_TABLE_H__
#define __SJ_TMP_TABLE_H__

#include <server_includes.h>
#include <table.h>

/*
  Describes use of one temporary table to weed out join duplicates.
  The temporary

  Used to
    - create a temp table
    - when we reach the weed-out tab, walk through rowid-ed tabs and
      and copy rowids.
      For each table we need
       - rowid offset
       - null bit address.
*/

class SJ_TMP_TABLE : public Sql_alloc
{
public:
  /* Array of pointers to tables that should be "used" */
  class TAB
  {
  public:
    struct st_join_table *join_tab;
    uint32_t rowid_offset;
    uint16_t null_byte;
    unsigned char null_bit;
  };
  TAB *tabs;
  TAB *tabs_end;

  uint32_t null_bits;
  uint32_t null_bytes;
  uint32_t rowid_len;

  Table *tmp_table;

  /* Pointer to next table (next->start_idx > this->end_idx) */
  SJ_TMP_TABLE *next;
};

Table *create_duplicate_weedout_tmp_table(Session *session,
                                          uint32_t uniq_tuple_length_arg,
                                          SJ_TMP_TABLE *sjtbl);

#endif /* __SJ_TMP_TABLE_H__ */
